My Home Ideas

Special Offers

Be the first to know about This Old House contests, sweepstakes, and events and receive special offers and promotions from your favorite home improvement brands. We'll even send you regular reminders to enter our sweepstakes.

If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.

Re: pin hole leaks in copper pipe

a 90 is full port meaning it does not taper down to a smaller diameter threw its bend and has the same id as a fully reamed copper tube.. the flow restriction is very minimal and a system installed with fully reamed tubes does not have major flow fluctuating thus eliminating erosion but it could be many things like water from a well source with old or no ph neutralizers
-sean the plumber

Re: pin hole leaks in copper pipe

well sleddoc, while the other guys are arguing over velocity restriction and flux bubbles i will point out 2 very important points. the pipe has been in the ground for 19 years. and it has only happened there. your house has a water softner and the pipes inside are fine. but the ground outside, in the dirt might have some extra mineals and be eating your pipes away. this is common near colorado springs, colorado. i don't know about where you live.

next what to do. replace the copper with pvc 1" line from the meater to the house connection. and before going into the house have a shut off valve inside a valve box.

Re: pin hole leaks in copper pipe

Originally Posted by misfitter

well sleddoc, while the other guys are arguing over velocity restriction and flux bubbles i will point out 2 very important points. the pipe has been in the ground for 19 years. and it has only happened there. your house has a water softner and the pipes inside are fine. but the ground outside, in the dirt might have some extra mineals and be eating your pipes away. this is common near colorado springs, colorado. i don't know about where you live.

next what to do. replace the copper with pvc 1" line from the meater to the house connection. and before going into the house have a shut off valve inside a valve box.

First how did you deduce that the pipe was buried? That these will be the only leaks?
Jack

Be sure you live your life, because you are a long time dead.-Scottish Proverb

Re: pin hole leaks in copper pipe

The explanation below might explain my leaks. I built my house in 2004. The plumber installed an instant hot water system. There is a pump that recirculates hot water from the farthest point away from the water heater through a third (plastic) tube back into the water heater. I have attached a picture of the pump. Last year, I noticed water all over the water heater and garage floor. I found a pin hole leak in the copper tubing. I patched the hole temporarily with a hose clamp and a piece of inner tube. Several weeks later, I noticed water again. I found a second pin hole near the first one. I replaced the piece of copper tubing. The piece with the pin holes in it was paper thin about an inch from the end of the tube. This week, I noticed water again and found a pin hole leak in another piece of the tubing. I have not repaired it yet but the leak is about an inch from the end of the tubing. After reading this explanation of the possible cause of the pin holes, I checked the piece of tubing I replaced last year. Although it was fairly thin near the end, it felt to me like the end had not been reamed before installation. Now I am wondering how well I reamed the ends of the piece I used last year to replace the bad one with. I think at this point I will replace all of the 1/2 inch tubing shown in the picture. There was no timer on the pump so the pump has been running 24/7 365 days a year. I also plan to put a timer on the pump when I replace the tubing. When I replace the tubing I will post another message in this forum telling what I find.

Originally Posted by djrenek1

this is most likely due to not reaming the copper tube to its full bore. its called velocity erosion when copper tube is cut with a tubing cutter it leaves a rounded over edge to the tube most people will just insert into the pipe and not think anything of it ( and i have seen other plumbers do this SCARY STUFF) the pipe needs to be reamed to its full bore or over time velocity erosion can occur. Now what happends is water travels threw the pipe when it hits the un reamed section this slows down the water flow then more faster water travels behind it with creates most force on the tube wich then causes water velocity erosion that slowly eats at the inner wall of the tubing and creates pitting and small pinholes hope this helps
- sean the plumber

Re: pin hole leaks in copper pipe

Originally Posted by JLMCDANIEL

It's quite common especially if to much flux was used when soldering. When the joint is heated the flux boils and pops and troughs small bubbles of flux which settle on the inside surface of the pipe. The flux is acidic and eventually eats through the pipe.
Jack

I hav to agree with Jack. Depending on what type of flux was used. probably nokorode that long ago, flux is very acidic. Velocity erosion or not I think knowing witch side of the joint the pin hole was on would tell us if this is in fact the cause or not. Something else to remember is it may have just been cheap copper tubing Pictures would help a bunch.

Re: pin hole leaks in copper pipe

Yesterday, I replaced the leaking tubing. I decided that since it appeared that the tubing ends may not have been reamed before being installed that I would replace all the tubing and the elbows. This turned out to be a wise plan since I found other pieces of tubing that were very thin. (I was glad to see that the tubing that I replaced last year had been reamed.) I have included two pictures of one piece of tubing. This is the short piece just above the pump. The first picture shows the end of the tubing that went into the elbow. The water entered the tubing at this end and exited at the other end. As you can see, the tubing is very thin at this end and in one spot there is a hole through the tubing. It is also apparent that the end was not reamed. The second picture shows the other end of the tubing. This is the end that the water exited from. The tubing appears to be normal thickness and has not been reamed. Another thing that I noticed is that the elbows showed signs of erosion on the outside bend of the elbow. This was more towards the end that the water entered the elbow.

It appears to me that djrenek1 had the correct answer for the leaks in my tubing. I might add that the pump and tubing were all installed by a licensed plumber. In fact, he installed the same type of system in several other houses that were built in my neighborhood the same time as mine. I plan to talk to the owners to see if they have had similar problems.

Originally Posted by oldhanggliderpilot

The explanation below might explain my leaks. I built my house in 2004. The plumber installed an instant hot water system. There is a pump that recirculates hot water from the farthest point away from the water heater through a third (plastic) tube back into the water heater. I have attached a picture of the pump. Last year, I noticed water all over the water heater and garage floor. I found a pin hole leak in the copper tubing. I patched the hole temporarily with a hose clamp and a piece of inner tube. Several weeks later, I noticed water again. I found a second pin hole near the first one. I replaced the piece of copper tubing. The piece with the pin holes in it was paper thin about an inch from the end of the tube. This week, I noticed water again and found a pin hole leak in another piece of the tubing. I have not repaired it yet but the leak is about an inch from the end of the tubing. After reading this explanation of the possible cause of the pin holes, I checked the piece of tubing I replaced last year. Although it was fairly thin near the end, it felt to me like the end had not been reamed before installation. Now I am wondering how well I reamed the ends of the piece I used last year to replace the bad one with. I think at this point I will replace all of the 1/2 inch tubing shown in the picture. There was no timer on the pump so the pump has been running 24/7 365 days a year. I also plan to put a timer on the pump when I replace the tubing. When I replace the tubing I will post another message in this forum telling what I find.

Re: pin hole leaks in copper pipe

That copper looks really BLACK on the outside and inside.

See no attachment on the water heater single wall vent connector before the bend elbow and not sealed see exposed crimping. Could that BLACKness on the outside be SOOT based chemical corrosive actions on the copper?

First thing is that flue exhast from gas water heater is corrosive and full of water vapor. The relationship/proximity of the corroding black copper and that breach for the vent makes me wonder if that isn't part of the problem.

Don't see any bonding jumpers thought Richard always installed near plumbing interuptions when by water heater?

2004 built house. See drywall behind water heater. Some of the recent lawsuits filed trace CHINESE DRYWALL back to 2001.

I read recently that one of the signs is BLACK discoloration on COPPER from hydrogen sulfide/sulfuric acid like fumes on copper. Something about iron pyrite or similar in the chinese drywall.

I read also that having laundry near gas water heater, using bleach, other chemicals causes same thing - and eats away at exposed copper really fast.

Moisture in the air or condensation on the pipe and black color on the copper in the pictures is why I mentioned this.

Why you wouldn't have the hot water lines insulated? I saw that in another article think it was mainly about saving energy.

Re: pin hole leaks in copper pipe

I was talking about how it shows as installed in the picture of the water heater set-up.

If the joints were cleaned/wiped after sweating then that would have come off. If they weren't wiped with a damp rag then the flux was left behind and it would show green or blue there at the edge of the copper. The copper looks black all along that area behind the water heater to the pump inches away from any solder joint like it shows in the big picture I don't think so.